suggest-pr-reviewers

name	suggest-pr-reviewers
description	Find relevant PR reviewers based on code ownership and recency of contributions. Use when creating PRs or needing to identify who should review code changes.

Suggest PR Reviewers

Find the most relevant reviewers for a pull request based on who has contributed to the changed files, using a weighted score that combines code ownership and recency.

Usage

reviewers [-n limit] [branch] [base]

• -n limit: Maximum reviewers to show (default: 10)
• branch: Branch to analyze (default: HEAD)
• base: Base branch to diff against (default: main)

Quick Start

Current branch vs main (top 10)

.agents/skills/suggest-pr-reviewers/scripts/reviewers.sh

Specify branches and limit

.agents/skills/suggest-pr-reviewers/scripts/reviewers.sh -n 5 feature-branch main

Metrics Explained

Uses chunk-level git blame to identify who wrote the specific lines being modified, not just who committed to the file.

Metric	Description	Formula
Score	Combined score (60% ownership, 40% recency)	ownership × 0.6 + recency × 0.4
Own	Log-scaled authorship with expert decay, capped	min(100, log(lines) × decay)
Recency	Score 15-100, higher = more recent	max(15, 100 × e^(-days × 0.693 / 30))
Lines	Lines of code being modified that this author wrote	Raw count from git blame
Files	Number of changed files this author touched	Unique file count
Days	Days since author last touched these lines	(now - last_blame_timestamp) / 86400

Scoring Features

• Recency floor (15): Historical experts don't drop to 0
• Ownership cap (100): Prevents prolific authors from dominating
• Expert decay: Ownership decays at 4× slower rate than recency (120-day half-life)

Task Instructions

When this skill is invoked:

1. Determine branches

   • If branch specified in args, use it; otherwise use current branch
   • If base specified, use it; otherwise use main

2. Run the reviewers script

   .claude/skills/suggest-pr-reviewers/scripts/reviewers.sh [branch] [base]
   

3. Present results

   • Show the full table of reviewers sorted by score
   • Note: The current git user can be found with git config user.name

4. Provide recommendations

   • Recommend 2-3 reviewers based on scores
   • If scores are close, mention both as equally qualified
   • If a reviewer has high recency but low ownership, note they have recent context
   • If a reviewer has high ownership but low recency, note they have deep knowledge

Example Output

Suggested reviewers for: feature-branch vs main
Files: 44 | Lines: 705

Author                    | Score |   Own | Recency | Lines | Files | Days
--------------------------|-------|-------|---------|-------|-------|-----
John                      |    99 |   100 |      97 |   210 |    15 |    1
Maria                     |    77 |    82 |      70 |    85 |     8 |   12
Steve                     |    66 |   100 |      15 |   205 |    20 |  180
Rose                      |    58 |    75 |      32 |    50 |     5 |   45

Algorithm Details

Recency Score (Exponential Decay with Floor)

Uses a 30-day half-life with a minimum floor of 15:

• 0 days ago = 100
• 30 days ago = 50
• 60 days ago = 25
• 90+ days ago = 15 (floor)

recency = max(15, 100 × e^(-days × ln(2) / 30))

Ownership Score (Logarithmic Scale with Decay and Cap)

Based on lines of code authored (from git blame), with:

• Logarithmic scaling (diminishing returns)
• Expert decay (120-day half-life, 4× slower than recency)
• Cap at 100

raw = 100 × log(lines + 1) / log(100)
decay = e^(-days × ln(2) / 120)
ownership = min(100, raw × decay)

Score (Weighted Combination)

score = ownership × 0.6 + recency × 0.4

The 60/40 weighting slightly favors code owners over recent-but-minor contributors.

Notes

• Uses chunk-level git blame on the exact lines being modified (not file-level)
• Pure additions (new files/lines) have no blame data and don't contribute to scores
• Ownership capped at 100; recency floored at 15 to keep historical experts visible
• Current user (from git config user.name) should typically be excluded from recommendations
• Works best with repositories that have >3 months of history